DLP 3D Printing Meets Lignocellulosic Biopolymers: Carboxymethyl Cellulose Inks for 3D Biocompatible Hydrogels

Abstract

The development of new bio-based inks is a stringent request for the expansion of additive manufacturing towards the development of 3D-printed biocompatible hydrogels. Herein, methacrylated carboxymethyl cellulose (M-CMC) is investigated as a bio-based photocurable ink for digital light processing (DLP) 3D printing. CMC is chemically modified using methacrylic anhydride. Successful methacrylation is confirmed by 1H NMR and FTIR spectroscopy. Aqueous formulations based on M-CMC/lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP) photoinitiator and M-CMC/Dulbecco’s Modified Eagle Medium (DMEM)/LAP show high photoreactivity upon UV irradiation as confirmed by photorheology and FTIR. The same formulations can be easily 3D-printed through a DLP apparatus to produce 3D shaped hydrogels with excellent swelling ability and mechanical properties. Envisaging the application of the hydrogels in the biomedical field, cytotoxicity is also evaluated. The light-induced printing of cellulose-based hydrogels represents a significant step forward in the production of new DLP inks suitable for biomedical applications.

Recent Developments of Carboxymethyl Cellulose

“…Moreover, the 3D-printed gels showed their potentialities in sustained-release drugs (i.e., lactoferrin) up to 21 days at optimum pH conditions. Melili et al (2020) [ 236 ] reported a photocurable bio-ink based on methacrylate-CMC that showed optimum potentialities to produce 3D-shaped hydrogels with good mechanical properties and swelling behavior. However, in that study, the authors revealed the applicability of CMC-based biomaterials in the bio-printing process via the digital light processing (DLP) method.…”

Sustainable Photopolymers in 3D Printing: A Review on Biobased, Biodegradable, and Recyclable Alternatives

“…[ 38 ] Terpenes, such as linalool monomer and a prepolymer from limonene [ 39 ] and polymyrcene mixed with reactive diluent β‐myrcene, [ 40 ] were used to print porous structures with high ductility following thiol‐ene chemistry. Methacrylated chitosan, [ 41,42 ] starch [ 43 ] and carboxymethyl cellulose [ 44 ] have also been used to print hydrogels, and good biocompatibility has been reported. Moreover, silk fibroin modified with methacrylates was applied in DLP printing to fabricate scaffolds and mimicked organ shapes with excellent biocompatibility.…”

Dispersion of Micro Fibrillated Cellulose (MFC) in Poly(lactic acid) (PLA) from Lab-Scale to Semi-Industrial Processing Using Biobased Plasticizers as Dispersing Aids

“…To overcome agglomeration problems, in the literature, good results have been obtained on a laboratory scale, with some trials in a semi-industrial scale [20][21][22][23] or even in 3D printing [24], using environmentally unfriendly solvents or chemicals (acetone, methanol, acetic acid, chloroform, sulphuric acid, dimethyl acetamide, and lithium chloride), making the industrial-scale production of MFC-based biocomposites difficult and unsustainable.…”